The present disclosure is related generally to the field of dental treatment. More particularly, the present disclosure is related to methods, devices, and systems for creating and utilizing dental positioning appliances.
Many dental treatments involve repositioning misaligned teeth and changing bite configurations for improved cosmetic appearance and dental function. Orthodontic repositioning can be accomplished, for example, by applying controlled forces to one or more teeth over a period of time.
An example of orthodontic repositioning that can occur can be through a dental process that uses one or more positioning appliances for realigning teeth. Such appliances may utilize a shell of material having resilient properties, referred to as an “aligner” that generally conforms to a patient's teeth but is slightly out of alignment with the initial tooth configuration.
Placement of such an appliance over the teeth can provide controlled forces in specific locations to gradually move the teeth into a new configuration. Repetition of this process with successive appliances in progressive configurations can move the teeth through a series of intermediate arrangements to a final desired arrangement.
Such systems typically utilize materials, such as thermoplastic polyurethane, polyester, and co-polyester, among others, that are thin, light weight, and/or transparent to provide as a set of appliances that can be used serially such that as the teeth move, a new appliance can be implemented to further move the teeth.
These materials are applied via a rapid prototyping or other construction process in generally uniform layers over a mold or built up without a mold to an aligner shape having a substantially uniform thickness. In some applications the forces provided by such uniform thickness structure may not provide a suitable amount of force (i.e., too much or too little force) in magnitude, direction, and/or duration.